1. Field of the Disclosure
This disclosure relates to a liquid crystal display (LCD) device, and more particularly to an LCD device adapted to prevent a blended color within each block, which is defined in a screen.
2. Description of the Related Art
In general, flat panel display devices are classified into a luminous type and a non-luminous type. The luminous type display devices include cathode ray tubes (CRTs), plasma display panels (PDPs), field emission display (FED) devices, and others. The non-luminous type display devices include LCD devices.
The LCD device has features such as light weight, less power consumption, and so on. However, the LCD device can not implement its own images due to its non-luminous property. In other words, the LCD device must use incident light from the exterior, in order to display images. As such, the image displayed on the LCD device is not visible in dark circumstances. To address this matter, the LCD device is configured to include a backlight unit disposed on it.
The backlight unit has widely employed a linear light source such as a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp, or others. Such fluorescent lamps have disadvantages such as large size, large power consumption, critical brightness, and others.
Due to this, light emission diodes (LEDs) corresponding to a spotted light source are being used in the backlight unit, instead of the fluorescent lamps. The LEDs can not primarily provide enough brightness to be used in the backlight unit. Also, a manufacturing cost of the primary LEDs is very high.
However, LEDs provided with sufficiently high brightness, a low manufacturing cost, and less power consumption have been developed recently. In order to generate a two-dimensional light, white LEDs can be used for forming an array, or red, green, and blue LEDs can be appropriately used for forming an array. The backlight unit employing such LEDs can be configured in a variety of LED arrays, in order to provide light of a desired shape. As such, the performance of the backlight unit depends upon the LED driving method.
Actually, the backlight unit allows the LEDs to be divisionally arranged in blocks into which an LCD panel of the LCD device is defined, and independently drives the LED blocks, in order to independently display blocked images (hereinafter, block images) which are each opposite to the divided blocks. In this case, each of the block image data can include pure chromatic color components with a high chroma level and non-chromatic color components. Due to this, a blended color can be caused in a boundary between the chromatic and non-chromatic color domains within the block image.
More particularly, as the number of blocks defined on the LCD panel must be limited, the chromatic and non-chromatic color domains are often generated to mix each other in only a specific block of the LCD panel. As such, the blended color (or, a deteriorated hue) often appears on only the specific block of the LCD panel. This color mixing phenomenon within each block image is generated in the blocks when the backlight unit employs not only the white LEDs but also the red, green, and blue LEDs.